entry: move a point to do 'auto_save' to another place

Summary:
By reworking on efl_file, logic flow for entry has been changed.
and it causes autosave making a file that is passed to elm_entry_file_set empty.

Test Plan:
1. call elm_entry_file_set for a file.
2. check the file is not empty after calling the function.

Reviewers: zmike, bu5hm4n

Reviewed By: zmike

Subscribers: cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D8362

Change-Id: Icb8202fb9cf55401c26c628358fa39e2947b2f7b